Gene scan saves Turkish boy

A super-fast reading of the genome of a five-month-old Turkish boy helped identify a critical illness and save his life.

Scientists at the Yale University Medical School, together with doctors in Beirut and Turkey, were able to complete their analysis of his blood in just 10 days.

Writing in the journal Proceedings of the National Academy of Sciences, researchers said they were able to see that he had a mutation on a gene that coded for a gut disease and tell his doctors.

The boy is now recovering following further clincial tests showed he did indeed have the disease.

Yale-based research team coordinator Richard Lifton said the boy's physicians sent a blood sample because they had little idea what was ailing the boy, and suspected a genetic disorder affecting the kidneys.

They were able to use a new method which allowed them to look at all the genes in the genome simultaneously.

Researchers identified a particular gene which had mutations on both copies and which meant that the child could not absorb water or electrolytes through his gastro-intestinal tract.

The condition is known as chongenital chloride diarrhoea, and only affects one in 50,000 people. It is treatable, but can affect the kidneys, bowels and even fertility if it goes undiagnosed.

Scientists then followed up a further 39 patients with a similar diagnosis and found that they too had the same mutation and the same genetic condition. They too are now receiving treatment.

Chris Ponting, Professor of Genomics at the Medical Research Council's Functional Genomics Unit said hailed the results as a turning point in the genetics of disease, as finding DNA changes had previously been a painfully slow task.

He said the new DNA sequencing technologies would pave the way for a flood of newly identified disease genes.

Oxford geneticist Mike McCarthy said that many researchers would focus on the 1% of the genome which codes for proteins, as the Yale-led research team had done.